That could be defeatable by crowdsourced research into a common database non blockchain of course ;-) ) and a chrome extension to ad an info UI to every ad, and

That could be defeatable by crowdsourced research into a common database non blockchain of course ;-) ) and a chrome extension to ad an info UI to every ad, and a Google feature to show you a restorspective look at id info of all ads they've served you recently.